Polycarbonamides resistant to acid dyes



United States Patent 3,440,226 POLYCARBONAMIDES RESISTANT T0 ACID DYESLawrence W. Crovatt, Jr., Raleigh, NC, and William A.

H. Huffman, deceased, late of Durham, N.C., by Ernestine H. Huffman,executrix, Antioch, Tenn., assignors to Monsanto Company, St. Louis,Mo., a corporafion of Delaware No Drawing. Filed Oct. 21, 1965, Ser. No.502,777

Int. Cl. C08g 20/38; D01 7/04 U.S. Cl. 260-78 11 Claims ABSTRACT OF THEDISCLOSURE Fiber-forming linear polycarbonamides modified to containcertain terminal naphthyl disulfonated radicals as an integral part ofthe polymer chain possess excellent acid dye-resistant properties.Fibers formed from these polycarbonamides may, for example, be combinedwith standard polycarbonamide fibers to provide a fabric which isdyeable in a single dye bath to different colors or color tones.

This invention relates to fiber-forming synthetic polymeric materialsand the shaped articles produced therefrom. More particularly, thisinvention relates to novel fiber-forming synthetic linearpolycarbonamides and shaped articles produced therefrom which areparticularly resistant to acid type dyes.

Although textile fibers obtained from fiber-forming polycarbonamidesheretofore known are of great value, they are deficient in dyingproperties in that they all possess the same acid dyeable characteristicand each type will dye to a single shade only. This is a distinctdisadvantage since it eliminates the possibility of obtaining otherdesirable color effects where some of the fibers do not absorb dye orabsorb less dye. It is desirable therefore, to produce polycarbonamideswhich have acid dye resist characteristics so that by combining suchpolycarbonamides with standard polycarbonamides in varying amounts itwould be possible to produce polycarbonamide articles which are dyeableto different tones of the same color.

Heretofore, additives employed for this purpose have not been found tobe entirely satisfactory due to their ability to impart only a limitedamount of acid dyeresistance to the fibers. For example, U.S. Patent No.3,039,990 discloses fibers with alkali metal dicarboxybenzenemonosulfonates. While these additives serve to make the fibers receptiveto basic dyes, they do not impart a sufficient acid dye-resist characterto the fibers to make them commercially acceptable for use with aciddyes in the production of a wide range of off-shade fabrics.

It is an object of the present invention to provide novel and usefulfiber-forming synthetic linear polycarbonamides.

Another object is to provide shaped articles such as textile fibers,produced from such polycarbonamides, the said article having superioracid dye-resist properties. A further object is to provide a process forthe production of polycarbonamides from which shaped articles havingsuperior acid dye-resist properties can be prepared.

These and other objects will become apparent in the course of thefollowing specification and claims.

The polycarbonamides of the present invention are useful in theproduction of shaped articles by extrusion, molding, or casting in thenature of yarns, fabrics, films, pellicles, bearings, ornaments, or thelike. They are particularly useful in the production of textile fibers.

The present invention provides a novel polycarbonamide wherein recurringcarbonamide linkages are an integral part of the polymer chain andcontaining as a 3,440,226 Patented Apr. 22, 1969 component part of thepolymer chain between about 0.05 and 2.0 mole percentage and preferablybetween about 0.1 and about 1.0 mole percentage, based on the molecularweight of the polycarbonamide, of units of the structure:

Moss SOaM wherein Z is a member of the class consisting of X is a memberof the class consisting of hydrogen and lower alkyl, M is a member ofthe class consisting of hydrogen, the ammonium radical and an alkalimetal and n is a number from zero to 6 inclusive with the proviso thatwhen Z is and HOOCR-COOH wherein R is a divalent hydrocarbon radical,and a diamine having the formula:

l e H-NR-NH (0) wherein X and R are as defined above, and (B) amonoaminomonocarboxylic acid having the formula:

wherein X and R are as defined above, in the presence of amonofunctional disulfonated compound having the formula:

(CHzhZY MOaS S 03M wherein n, Z and M are as defined above and Y is amember of the class consisting of hydrogen, OH, CL and OR, R' being amonovalent hydrocarbon radical such that R'OH is volatile below thedecomposition temperature of the polycarbonamide formed.

The nature of the radical R- in the acid, the diamine, or the aminoacidis not critical. Preferably, it is a divalent hydrocarbon radicalcontaining no more than about 20 carbon atoms. Typical acids of theclass illustrated by the formula designated (b) are oxalic, adipic,suberic, pimelic, azelaic, sebacic, brassylic, octadecanedioic,undecanedioic, glutaric, tetradecanedioic, p-phenylene diacetic,isophthalic, terephthalic, hexahydroterephthalic, and the like, andmixtures thereof.

Typical suitable diamines of the class illustrated by the formuladesignated (c) above are ethylene diamine, propylene diamine,tetramethylene diamine, pentamethylenediamine, hexamethylene diamine,octamethylene diamine, decamethylene diamine, p-xylylenediamine,pphenylenediamine, hexahydro p phenylenediamine, bis(4aminocyclohexyl)methane, piperazine, dimethylpiperazine,tetramethylpiperazine, the N,N'-dimethyl, the N,N'-diethyl and theN,N'-diisopropyl derivatives of the above, and the like, as well asmixtures thereof.

Typical suitable amino acids of the class represented by the formuladesignated (d) above are 6-aminocaproic acid, 9-aminononanoic acid,ll-aminoundecanoic acid and 17-aminoheptadecanoic acid.

In place of the above noted dibasic carboxylic acids, diamines, andamino acids, the amide-forming derivatives thereof can be employed toform fiber-forming polymers. Amide-forming derivatives of the dibasiccarboxylic acids comprise the mono and di-ester, the anhydride, themonoand di-amide and the acid halide. Amide-forming derivatives of thediamines include carbamate and the N-formyl derivative. Amide-formingderivatives of the amino acids include the ester, anhydride, amide,lactam, acid halide, N-formyl derivative, carbamate, and, in thepresence of water, the nitrile.

As indicated above the compounds found useful in the practice of thisinvention are characterized by two sulfonate groups and oneamide-forming group attached to a naphthalene ring and are representedby the formula:

M 8 SOaM wherein n, Z, M and Y are as defined above. Illustrative ofsuch compounds when are: di(potassium sulfonate) naphthalene 2carboxylic acid, di(ammonium sulfonate) naphthalene 2- carboxylic acid,di(potassium sulfonate) naphthalene- 1 carboxylic acid, di(sulfonicacid) naphthalene 2- carboxylic acid, di(potassium sulfonate)naphthalene- 2-ethanoic acid, di(ammonium sulfonate)-naphthalene- 1propionic acid, di(sodium sulfonate) naphthalene- 2 pentanoic acid, anddi(sulfonic acid) naphthalene- 1 heptanoic acid; and when illustrativecompounds are di(potassium sulfonate)- naphthalene 2 methylamine,di(ammonium sulfonate)- naphthalene 2 methylamine, di(sulfonic acid)naphthalene 2 ethylamine, di(potassium sulfonate) naphthalene 1ethylamine, and di(sodium sulfonate)- naphthalene-Z-pentylamine.

The polycarbonamides of this invention are prepared by procedures wellknown in the art and commonly employed in the manufacture of simplepolyamides. That is, the reactants are heated at a temperature of from180 C. to 300 C. and preferably from 200 C. to 295 C. until the producthas a sufiiciently high molecular weight to exhibit fiber-formingproperties, which properties are reached when the polyamide has anintrinsic viscosity of at least 0.4. The reaction can be conducted atsuperatmospheric, atmospheric, or sub-atmospheric pressure. Often it isdesirable, especially in the last stage of the reaction, to employconditions, e.g. reduce pressure, which will aid in the removal of thereaction by-products. Preferably, the reaction is carried out in theabsence of oxygen, for example, in an atmosphere of nitrogen.

Intrinsic viscosity as employed herein is defined as Lim. Logs Nr 0 o inwhich N is the relative viscosity of a dilute solution of the polymer inm-cresol in the same units at the same temperature, and C is theconcentration in grams of polymer per cc. of solution.

The amount of additive which may be present as a component part of thepolymer chain of the polycarbonamides of this invention may varydepending upon the type of polymer desired and the particular shapedarticle in which it is to find its end use. It has been found necessaryto employ between about 0.05 and 2.0 mole percentage based on themolecular weight of the polycarbonamide. At least 0.05 mole percentageof additive is required in order that a significant level of aciddye-resist properties be obtained. It has been found that the bestresults are obtained when between about 0.1 and about 1.0 molepercentage of additive based on the molecular weight of thepolycarbonamide are employed. Amounts greater than 2.0 mole percentagehave an adverse effect on the viscosity of the polycarbonamide produced.Since the additives employed in this invention contain only onefunctional group, i.e., one carboxyl or one amino group, it can be seenthat they react in such a manner as to terminate the polymer chain ofthe polycarbonamide. This type of reaction is similar to the reactionwhich occurs upon the addition of additives which are termed by the artas chain terminators or viscosity stabilizers. Thus, the greater amountof additive which is employed in the present invention, the shorter willbe the polymer chain of the polycarbonamide and the lower will be theviscosity of the polycarbonamide. As noted above, it has been foundpreferable to employ amounts of additives between about 0.1 and 1.0 molepercentage since when employing such amounts the polycarbonamideproduced has been found to possess excellent acid dye-resist propertiesand to have a viscosity in the fiber-forming range.

In order to illustrate the invention and the advantages thereof withgreater particularity, the following specific examples are given; it isto be understood that they are intended to be only illustrative and notlimitative. Parts are given by Weight unless otherwise indicated.

EXAMPLE I This example illustrates preparation of a conventionalpolycarbonamide namely, polyhexamethylene adipamide. This polymer andthe fiber therefrom are to be used as a standard of comparison with themodified polycarbonamides of the present invention.

To a stainless steel evaporator there was added 8.47 moles of watercontaining 0.562 mole of hexamethylene diammonium adipate salt dissolvedtherein. The unit was purged with nitrogen and then pressurized to 13pounds per square inch gauge. The salt solution was then heated to 137C. with continuous removal of steam condensate. At this point the saltconcentrate was piped under pressure into a stainless steel highpressure autoclave which had been purged previously with nitrogen. Inthis reactor, which contained a stirrer for agitation, the pressure wasimmediately raised to 250 pounds per square inch gauge and thetemperature was raised to 220 C. The steam was removed until the polymermelt temperature reached 243 C. At this point the reactor pressure wasgradually reduced over a 25 minute period to atmospheric pressure andthe polymer melt allowed to equilibrate for 30 minutes at 278 C.

This finished polymer so produced was melt spun at 280 C. through a 13hole spinnerette yielding white multifilament yarns. These yarns weredrawn over hot pins (90 C.) at a maximum draw ratio of 5.65 times theiroriginal length.

Dyeing of these yarns was carried out by immersing in an acid dye bathcontaining 3 percent, based on the weight of the yarn, of Scarlet 4RAConc. CF .(C.I. Acid ployed in Example II exhibited an increase acid dyeresistance of nearly 122 percent over the additive employed in ExampleIII.

EXAMPLE VII 5 Acid dye-resist poly-epsilon-caproamide was prepared Red18) and Percent f f acld' Welght rattle by introducing 100 grams ofepsilon-caprolactam and 1.94 of dye bath to fiber was maintau ied at40.1 and dfl 3 grams of di(potassium sulfonate)-naphthalene-2-carboxwasconducted for 2 hours at 100 and at 3 PH ylic acid into a stainlesssteel high pressure autoclave. These Y absorbed 'P dyestufi' Afterpurging with nitrogen the autoclave was pressurized EXAMPLE II 10 to 250pounds per square inch gauge and the temperature was raised to 250 C.while steam was continuall re- Dflpotassmmsulfmiate)'naphthalenia-carbozglic g moved. At this point the pressurewas gradually red iiced fi prepared by treatmg 100 grams 0 i'gi sg igover a 25 minute period to atmospheric pressure and the 211th 752 r iif- 5 pertzfmt z 5 3 2 a to r temperature of the molten polymer reached265 C. The ours at 100 e mac Ion pro f f 250 vacuum cycle was thenapplied to the autoclave by gradu- 1000 grams of followed by w mom 0grams ally lowering the pressure over a 30 minute period to 25 ofpotassium bicarbonate. A precipitated product formed inches of mfircuryand the p y melt allowed to which was redissolved by adding 3 hters ofWater and heate uilibrate under tliese conditions for minutes before thesolution to 70 C. followed by treatment with 2 q mg returning theautoclave to atmospheric pressure by allowgrams of activated charcoal.To the hot filtered solutiordr ing nitrogen to bleed back into theSystem The polymer was p added 225 gran}? of potassium chloride an wasimmediately melt spun at 265 C. directly from the precipitation of thefinely divided 'whlte product, di(potasautoclave as 13 multifilamentWhite y sium sulfonate)naphthalene-2-carboxyl1c acid, occurred. The y gprocedure and Conditions outlined in Exam T product was filtered OE andpunfied by redlssolvl-Hg ple I were repeated and these yarns were foundto absorb 1n 2300 cc. of water at 70 C. followed by treatment with O 60percent Scarlet 4RA Cone CF I Acid Red 1 gram of activated charcoal.After filtration while hot, p to 1.08 percent absor'ption lwl'lich wasobserved 100 grams 9 chlonde was g gg g gon conventionalpoly-epsilon-caprylamide yarns contain- Proquct preqlpltated m form ne 5lte ing 0.536 mole percent potassium-3,S-dicarboxybeuzene pamcles whichafter coohng were Isolate tratlon' sulfonate which were prepared anddyed under identical The procedure of Example I was repeated with theexconditions ception that the above-prepared di(potassium sulfonate)-EXAMPLE VIII naphthalene2-carboxylic acid in an amount sufficient toprovide a finished polyhexamethylene adipamide contain-Poly-hexamethylene sebacamide modified in accordance ing 0.555 molepercent additive, was added along with with the present invention wasprepared by charging a the salt into the autoclave. This modified nylonpolymer stainless steel evaporator with 0.393 mole of hexamethylthusproduced was melt spun at 280 C. through a 13-hole ene diammoniumsebacate dissolved in 20.8 moles of water spinnerette yielding whitemultifilarnent yarns. These yarns containing 0.968 gram of di(potassiumsulfonate)- were drawn over hot pins (90 C.) at a maximum drawnaphthalene-Z-carboxylic acid. After purging the evaporaratio of 4.60times their original length. These yarns were tor with nitrogen the unitwas pressurized to 13 pounds found to absorb 0.36 percent Scarlet 4RAConc. CF (C. I. per square inch gauge and heated to 137 C. with removalAcid Red 18) acid dye stuff when dyed under identical of steamcondensate. At this temperature the concentrated procedure and dye bathcomposition as outlined in Exsalt was then piped under pressure to ahigh pressure ample I, autoclave, which was previously purged withnitrogen, and EXAMPLE III 4 the unit pressurized to 250 pounds persquare inch gauge 5 and the temperature raised to 230 C. with thecontinual ag g i?2 L3 gf gzz ggs gg g removal of steam. At thistemperature the pressure in the f E Z e sulfolllate y gi is descgibed inautoclave was gradually reduced over a 25 minute period lca oxy en ene hto atmospheric pressure while the polymer melt tempera- Patent.303.9 yamg i g W tfiate ture was raised to 265 C. The melt was then allowed tounder ldentlca con moms as emp eye In Xamp e was stand and equilibratefor a period of 30 minutes prior to fg g g fgg Percent Scarlet 4RA ConeCF melt spinning at 265 C. directly from the autoclave c1 e I EXAMPLESIV VI glllrrolugh a 13 hole spinnerette yielding whlte multlfilament Theprocedures outlined in the above examples were re- The spun yarns weredrawn over hot pins (90 C.) at peated with the exception of theparticular additive ema maximum draw ratio of 4.50 times their originallength. ployed and in the amount in which it was employed. The The yarnswere dyed in accordance with the procedure results obtained areillustrated in Table I. and conditions outlined in Example I, and werefound to TABLE I Mole Increase Dye-Resist.

Percent Amoun Additive Additive of Dye Ex. IV Ex. IV

in Absorption vs. vs. Polymer Ex. V, Ex. VI, Percent Percent Example:

IV (a) Di(potassium sulfonate)-naphthalene-2-carboxylic acld 0.139 0.71IV (b)- --do. 0.780 0.21 V (a)... Potassium 3 5 dicarboxy-benzenesulfonate 0.139 0.98 V(b)- o- 0.780 0.52 VI (3) -sulfobenzo1e acidmonosodium salt. 0. 139 0. 94 VI (b)- do 0. 780 0. 49

These experimental findings clearly show the pronounced superiority ofthe additives of this invention over the difunctional monosulfonate saltand the monofunctional monosulfonate salt when used in correspondingamounts. Besides the increased acid dye resistance indicated in Table I,it should be noted that the additive emabsorb 0.39 Scarlet 4RA Conc. CF(C. 1. Acid Red 18). Yarns prepared in an identical manner with theexception that potassium-3,S-dicarboxybenzene sulfonate was the additiveused were found to absorb 0.70 percent of the same dye. It will beobserved that yarns containing the additive of the present inventionexhibit an increase in acid dye-resist properties of 79.5 percent overyarns containing additives disclosed by the prior art.

EXAMPLE IX Di(sulfonic acid)-napththalene-Z-carboxylic acid was preparedby treating a dilute aqueous solution of di(potassiumsulfonate)-naphthalene-Z-carboxylic acid with a cation exchange resin inan ion-exchange column. The treated solution was then evaporated todryness yielding a white product, di(sulfonicacid)-naphthalene-2-carboxylic acid. The preparation of modifiedpoly-hexamethylene adipamide containing 0.60 mole percent of di(sulfonicacid)-naphthalene-Z-carboxylic acid was carried out by the sameprocedure and conditions described in Example I. The additive wasincorporated into the polymer preparation in the same method asdescribed in Example II.

The resultant polymer was melt spun at 280 C. directly from thepreparatory autoclave into 13 multifilament white yarns which were drawnat a maximum draw ratio of 5.70 times their original length.

These yarns were found to absorb 0.73 percent of Scarlet 4RA Conc. CF(C.I. Acid Red 18) when dyed according to procedure and conditionsoutlined in Example I. This dye absorption represents very nearly 41.6percent improvement in the dye-resist character over conventionalpolyhexamethylene adipamide which absorbs 1.25 percent of the same dye.

EXAMPLE X Di( ammonium sulfonate)-naphthalene 2 carboxylic acid wasprepared by reacting 1 mole ratio of di(sulfonicacid)-naphthalene-Z-carboxylic acid with 2 mole ratios of ammoniumhydroxide in an aqueous solution and the diammonium salt product allowedto remain in solution. Modified polyhexamethylene adipamide containing0.60 mole percent of the diammonium salt was carried out by the sameprocedure and conditions described in Example I. The additive wasincorporated into the polymer preparation in the same manner asdescribed in Example II.

The resultant polymer was melt spun at 280 C. into 13 multifilamentwhite yarns which could be cold drawn. These yarns were found to absorb0.67 percent Scarlet 4RA Conc. CF (C.I. Acid Red 18) when dyed accordingto procedures and conditions outlined in Example I. This dye absorptionrepresents very nearly 46.4 percent improvement in the acid dye resistcharacter over the standard polyhexamethylene adipamide yarns whichabsorb 1.25 percent of the same dye.

As can be seen from the above results, fibers made from thepolycarbonamides of the present invention all possess a resistance toacid type dyes. This enables manufacturers to produce fibers having thesame basic polycarbonamide molecular structure as conventionalpolycarbonamides but different affinities for acid dyes. This in turnotters dyeing diversification for fabric color-on-white effects andtoneon-tone effects heretofore not readily obtainable.

We claim:

1. A fiber-forming synthetic linear polycarbonamide wherein recurringcarbonamide linkages are an integral part of the polymer chain andcontaining as a component part of the polymer chain between about 0.1and 2.0 mole percentage, based on the molecular weight of thepolycarbonamide of units of the structure:

Moss $03M wherein Z is a member of the class consisting of II C and X isa member of the class consisting of hydrogen and lower alkyl, M is amember of the class consisting of hydrogen, the ammonium radical and analkali metal and n is a number from zero to 6 inclusive with the provisothat when Z is then It is at least 1.

2. The fiber-forming synthetic linear polycarbonamide as set forth inclaim 1 wherein the polycarbonamide is poly-hexamethylene adipamide.

3. The fiber-forming synthetic linear polycarbonamide as set forth inclaim 1 wherein the polycarbonamide is poly-epsilon-caproamide.

4. The fiber-forming synthetic linear polycarbonamide as set forth inclaim 1 wherein the polycarbonamide is poly-hexamethylene sebacamide.

5. A fiber-forming synthetic linear polycarbonamide wherein recurringcarbonamide linkages are an integral part of the polymer chain andcontaining as a component part of the polymer chain between about 0.05and 2.0 mole percentage based on the molecular weight of thepolycarbonamide of units of the structure:

KOaS 803K 6. Polyhexamethylene adipamide containing as a component partof the polymer chain between about 0.05 and 2.0 mole percentage based onthe molecular weight of the polyhexamethylene adipamide of units of thestructure:

7. Polyhexamethylene adipamide containing as a component part of thepolymer chain between about 0.05 and 2.0 mole percentage, based on themolecular weight of the polyhexamethylene adipamide of units of thestructure:

HOaS SOaH 8. Polyhexamethylene adipamide containing as a component partof the polymer chain between about 0.05 and 9 10 2.0 mole percentage,based on the molecular weight of the of the polyhexamethylene sebacamideof units of the polyhexamethylene adipa-mide of units of the structure:structure:

K038 SOaK NHtoaS soaNH 11. A textile fiber consisting essentially of thepoly- 9. Poly-epsilon-caproamide containing as a component capbonamldeas defined m Clalm part of the polymer chain between about 0.05 and 2.0mole percentage, based on the molecular weight of the References cuedpoly-epsilon-caproamide of units of the structure: UNITED ES ATENTS 03,039,990 6/1962 Huffman 260-78 1 3,142,662 7/1964 Huffman 260783,184,436 5/1965 Magat 260-78 3,296,204 1/1967 Caldwell 26078 3,328,4846/1967 Lugaz et al. 260-78 K038 $03K WILLIAM H. SHORT, Przmary Examzner.

H. D. ANDERSON, Assistant Examiner.

10. Polyhexamethylene sebacamide containing as a component part of thepolymer chain between about 0.05 and 2.0 mole percentage based on themolecular weight 26078; 8--55; 57--140

